In United States trademark law, Abercrombie & Fitch Co. v. Hunting World has defined the framework of trademark distinctiveness. In the case, trademarks are divided into categories which have different degrees of protection. The different categories are: fanciful, arbitrary, suggestive, generic.
An arbitrary trademark is such a category. It usually defines a common word which is used in a meaningless context (e.g. "Apple" for computers). Such marks consist of words or images which have some dictionary meaning before being adopted as trademarks, but which are used in connection with products or services unrelated to that dictionary meaning.
Example of arbitrary trademarks are: